title: Application of carbodiimide derivatized synovial fluid to enhance extrasynovial tendon gliding ability.
abstract: OBJECTIVE
  To investigate the effects of surface modification of extrasynovial tendon with a carbodiimide derivatized synovial fluid (SF) on the gliding ability of extrasynovial tendon for a possible tendon graft application.
  
  
  METHODS
  We used 63 peroneus longus tendons from canine hind legs. We immediately assessed 3 tendons morphologically using a scanning electron microscope (SEM); these served as the normal tendon group. The other 60 tendons were randomly assigned to each of 6 experimental groups treated with (1) control (saline); (2) 1% 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) plus 1% N-hydroxysuccinimide (NHS) (cd only); (3) 1% EDC/NHS plus 10% gelatin (cd-G); (4) SF plus 1% EDC/NHS plus 10% gelatin (cd-SF-G); (5) SF only; or (6) SF plus 1% EDC/NHS (cd-SF). We measured the gliding resistance for 1,000 cycles of simulated flexion-extension motion. We also observed the tendon surface smoothness by SEM.
  
  
  RESULTS
  Compared with the first cycle in each group, the gliding resistance after 1,000 cycles of tendon motion was significantly increased in the control, cd only, cd-gelatin, SF only, and cd-SF groups (p<.05). In contrast, we found no significant difference in gliding resistance between the first cycle and 1,000 cycles for the cd-SF-G-treated group. In addition, the gliding resistance in the cd-SF, cd-G, and cd-SF-G groups was significantly lower than the control group after 1,000 cycles of tendon motion (p<.05) and the gliding resistance of the cd-SF-G group was significantly lower than both the cd-G and cd-SF groups (p<.05). On SEM, the surface treated with cd-SF-G was smooth after 1,000 cycles, whereas the other surfaces were rough.
  
  
  CONCLUSIONS
  Surface modification of extrasynovial tendon with cd-SF-G improves tendon gliding ability. This treatment may be useful clinically in improving the outcomes of tendon autografts.
authors.affiliation: Orthopedic Biomechanics Laboratory, Division of Orthopedic Research, Mayo Clinic, Rochester, MN 55905, USA.
authors.forename: Jun
authors.initials: J
authors.lastname: Ikeda
authors.forename: Yu-Long
authors.initials: YL
authors.lastname: Sun
authors.forename: Kai-Nan
authors.initials: KN
authors.lastname: An
authors.forename: Peter C
authors.initials: PC
authors.lastname: Amadio
authors.forename: Chunfeng
authors.initials: C
authors.lastname: Zhao
mesh_terms: D000818:Animals; D004285:Dogs; D005022:Ethyldimethylaminopropyl Carbodiimide / Q000494:pharmacology*; D017276:Friction / Q000187:drug effects*; D006614:Hindlimb; D066298:In Vitro Techniques; D013388:Succinimides / Q000494:pharmacology; D013499:Surface Properties / Q000187:drug effects; D013582:Synovial Fluid / Q000502:physiology*; D013710:Tendons / Q000187:drug effects* / Q000648:ultrastructure; D013718:Tensile Strength / Q000187:drug effects; D016474:Weight-Bearing
chemical_list: D013388:Succinimides; C001426:N-hydroxysuccinimide; D005022:Ethyldimethylaminopropyl Carbodiimide